Graph mining II: analysis and modeling

Dobre Bogdan-Mihai, Moldovan George, Mocanu Alexandru

07 decembrie 2020

Introducere

Reprezentarea datelor sub forma de retea e o abordare diferita fata de modul clasic de reprezentare, cel tabelar. Acest format poate evidentia noi caracteristici ale datelor si imbunatesteste vizualizarea acestora intr-un mod semnificativ.

Pentru a realiza o analiza originala, setul de date folosit reprezinta structura unei retele de trafic cu tigari de contrabanda din Romania, datele fiind extrase dintr-un dosar penal. Astfel, utilizand metode de graph mining vom realiza o analiza asupra structurii retelei, dar si asupra rolurilor individuale ale membrilor.

Capitolul 1 - Modelarea datelor in R

Datele au fost modelate folosind un obiect de tip reţea din librăria statnet. Legăturile dintre noduri au fost introduse folosind o lista de muchii, iar nodurile au următoarele atribute : nume, nume abreviat si rol.

library(statnet)
library(RColorBrewer)
library(network)
netmat <- rbind(c(1,2),
                c(1,3),
                c(2,3),
                c(1,4),
                c(5,6),
                c(7,8),
                c(5,7),
                c(5,8),
                c(5,9),
                c(6,7),
                c(6,8),
                c(6,9),
                c(5,10),
                c(6,10),
                c(11,12),
                c(11,13),
                c(13,14),
                c(14,19),
                c(13,19),
                c(14,1),
                c(19,15),
                c(19,16),
                c(19,17),
                c(19,18),
                c(12,15),
                c(12,16),
                c(12,17),
                c(12,18),
                c(20,8),
                c(20,9),
                c(21,8),
                c(21,9),
                c(3,8),
                c(3,9),
                c(1,8),
                c(1,9))


net <- network(netmat, matrix.type="edgelist")
netmatsym <- symmetrize(as.sociomatrix(net), rule ="weak")


netsym <- network(netmatsym, matrix.type="adjacency")
network.vertex.names(netsym) <- c("B***cu L***na", 
                                  "B***cu An***us", 
                                  "B**scu C***nel",
                                  "B**hiu G***ge",
                                  "M**tu M**na",
                                  "Ma**u I***he",
                                  "T**a F**p",
                                  "T**a G***ghe",
                                  "S**m An**la",
                                  "G**ca G****ghe",
                                  "C**u I**n",
                                  "M***u L**do",
                                  "D**a D**a",
                                  "D**a C**l",
                                  "N**cu P**u",
                                  "N**se T**er",
                                  "S***an C***tin",
                                  "O***u A**ei",
                                  "D**a I***l",
                                  "P**ci V***e",
                                  "D***mir R**a")
set.vertex.attribute(netsym, "role", c("C", 
                                       "C", 
                                       "C",
                                       "CR",
                                       "C",
                                       "C",
                                       "CT",
                                       "CT",
                                       "CT",
                                       "C",
                                       "C",
                                       "A",
                                       "A",
                                       "C",
                                       "C",
                                       "C",
                                       "C",
                                       "C",
                                       "CT",
                                       "D",
                                       "D"))
# C : Comerciant, CR : Cartita, CT: contrabandist, A: aducator clienti, D: depozitare
set.vertex.attribute(netsym, "abrev_name", c("BL", 
                                             "BA",
                                             "BC",
                                             "BG",
                                             "MM",
                                             "MI",
                                             "TF",
                                             "TG",
                                             "SA",
                                             "GG",
                                             "CI",
                                             "ML",
                                             "DD",
                                             "DC",
                                             "NP",
                                             "NT",
                                             "SC",
                                             "OA",
                                             "DI",
                                             "PV",
                                             "DR"))
netsym %v% "alldeg" <- degree(netsym)
namelab <- get.vertex.attribute(netsym, "vertex.names")
rolelab <- get.vertex.attribute(netsym, "role")
abrevnamelab <-get.vertex.attribute(netsym, "abrev_name")
my_pal <- brewer.pal(5,"Dark2")
rolecat <- as.factor(get.vertex.attribute(netsym,"role"))
plot(netsym,
     main = "Infractional network",
     usearrows=FALSE, 
     mode="fruchtermanreingold", 
     vertex.col = my_pal[rolecat],
     label=rolelab,
     displaylabels=T,
     vertex.cex = 1.5)

Capitolul 2 - Analiza primara a retelei

O prima analiza asupra retelei este realizarea rezumatului in 5 puncte. Functiile prezente in libraria statnet faciliteaza realizarea acesteia. Analizand aceste valori, putem avea o prima impresie despre structura retelei si despre modul de organizarea a acesteia.

print("BASIC CHARACTERISTICS")
## [1] "BASIC CHARACTERISTICS"
summary(netsym, print.adj = FALSE)
## Network attributes:
##   vertices = 21
##   directed = TRUE
##   hyper = FALSE
##   loops = FALSE
##   multiple = FALSE
##   bipartite = FALSE
##  total edges = 72 
##    missing edges = 0 
##    non-missing edges = 72 
##  density = 0.1714286 
## 
## Vertex attributes:
## 
##  abrev_name:
##    character valued attribute
##    attribute summary:
##    the 10 most common values are:
## BA BC BG BL CI DC DD DI DR GG 
##  1  1  1  1  1  1  1  1  1  1 
## 
##  alldeg:
##    numeric valued attribute
##    attribute summary:
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   2.000   4.000   6.000   6.857  10.000  14.000 
## 
##  role:
##    character valued attribute
##    attribute summary:
##  A  C CR CT  D 
##  2 12  1  4  2 
##   vertex.names:
##    character valued attribute
##    21 valid vertex names
## 
## No edge attributes
print("Size:")
## [1] "Size:"
print(network.size(netsym))
## [1] 21
print("Density:")
## [1] "Density:"
print(gden(netsym))
## [1] 0.1714286
print("Components:")
## [1] "Components:"
print(components(netsym))
## [1] 1
print("Diameter:")
## [1] "Diameter:"
gd <- geodist(netsym)
print(max(gd$gdist))
## [1] 7
print("Transitivity:")
## [1] "Transitivity:"
print(gtrans(netsym, mode="graph"))
## [1] 0.25

3. Capitolul 3 - Managementul datelor atribuite unei retele

Folosind atributele definite în momentul creării, putem filtra reţeua astfel încat putem evidenţia importanţa unui anume rol. Spre exemplu, dacă am păstra în reţea doar Comercianţii, putem observa că aceştia sunt în mare partea izolaţi, distrugând aspectul de reţea compactă. Acest lucru evidenţiază rolul contrabandiştilor în reţea, aceştia asigurând practic conexitatea reţelei.

print("Filtering networks")
print(get.vertex.attribute(netsym, "role"))
comercianti <- get.inducedSubgraph(netsym, which (netsym %v% "role"=="C"))
gplot(comercianti,displaylabels=TRUE, main="Comercianti")

delete.vertices(comercianti, isolates(comercianti))
gplot(comercianti, displaylabels = TRUE, main="Grupuri de comercianti")

4.Basic network plotting and layout

Circle

gplot(netsym,gmode="graph",edge.col="grey75",displaylabels=T,
      vertex.cex=1.5,mode='circle',main="circle")

Eigen

gplot(netsym,gmode="graph",edge.col="grey75",displaylabels=T,
      vertex.cex=1.5,mode='eigen',main="eigen")

Random

gplot(netsym,gmode="graph",edge.col="grey75",displaylabels=T,
      vertex.cex=1.5,mode='random',main="random")

Spring

gplot(netsym,gmode="graph",edge.col="grey75",displaylabels=T,
      vertex.cex=1.5,mode='spring',main="spring")

Fruchterman-Reingold

gplot(netsym,gmode="graph",edge.col="grey75",displaylabels=T,
      vertex.cex=1.5,mode='fruchtermanreingold',main='fruchtermanreingold')

Kamada-Kawai

gplot(netsym,gmode="graph",edge.col="grey75",displaylabels=T,
      vertex.cex=1.5,mode='kamadakawai',
      main='kamadakawai')

5.Effective network graphic design

library(network)

library(intergraph)
library(igraph)

library(networkD3)

plot(netsym,vertex.cex=0.5,main="Too small nodes")

plot(netsym,vertex.cex=6,main="Too large nodes")

plot(netsym,vertex.cex=2,main="Just right node size")

Different node type

sidenum <- 3:7
rolecat <- as.factor(get.vertex.attribute(asIgraph(netsym),"role"))
plot(netsym,usearrows=FALSE,vertex.cex=4, main="Different node type",
     displaylabels=F,vertex.sides=sidenum[rolecat])

Edge coloring example

n_edge <- network.edgecount(netsym)
linecol_pal <- c("blue","red","green")
edge_cat <- sample(1:3,n_edge,replace=T)
plot(netsym,vertex.cex=1.5,vertex.col="grey25", main="Edge coloring example",
     edge.col=linecol_pal[edge_cat],edge.lwd=2)

Different edge width

widths <- c(2,6,10)
plot(netsym,vertex.cex=1.5,main="Different edge width",
     edge.lwd=1.5*widths)

Different edge type

n_edge <- network.edgecount(netsym)
edge_cat <- sample(1:3,n_edge,replace=T)
line_pal <- c(2,3,4)
gplot(netsym,vertex.cex=0.8,gmode="graph", main="Different edge type",
      vertex.col="gray50",edge.lwd=1.5,
      edge.lty=line_pal[edge_cat])

Infractional network

my_pal <- brewer.pal(5,"Dark2")
rolecat <- as.factor(get.vertex.attribute(asIgraph(netsym),"role"))
plot(netsym,
     main = "Infractional network",
     usearrows=FALSE, 
     mode="fruchtermanreingold", 
     vertex.col = my_pal[rolecat],
     label=abrevnamelab,
     displaylabels=T,
     vertex.cex = 1.5)
legend("bottomleft",legend=c("Aducator clienti","Comerciant","Cartita","Contrabandist","Depozitare"),
       col=my_pal,pch=19,pt.cex=1.5,bty="n",
       title="Criminal Role")

6.Advanced Network Graphics

Tkplot

#Visnetwork
library(visNetwork)
inetsym_edge <- get.edgelist(inetsym)
inetsym_edge <- data.frame(from = inetsym_edge[,1],
                         to = inetsym_edge[,2])
inetsym_nodes <- data.frame(id = as.numeric(V(inetsym)))
visNetwork(inetsym_nodes, inetsym_edge, width = "100%")

Chord diagram

7. Actor proeminence

Cutpoints

Determining the centre nodes using the degree

Determining the centre nodes using the closeness function

Determining the centre nodes using the betweenness function

Bridges

Chapter 8

## Setup
### Import igraph for this part of the project
library(igraph)
## 
## Attaching package: 'igraph'
## The following objects are masked from 'package:sna':
## 
##     betweenness, bonpow, closeness, components, degree, dyad.census,
##     evcent, hierarchy, is.connected, neighborhood, triad.census
## The following objects are masked from 'package:network':
## 
##     %c%, %s%, add.edges, add.vertices, delete.edges, delete.vertices,
##     get.edge.attribute, get.edges, get.vertex.attribute, is.bipartite,
##     is.directed, list.edge.attributes, list.vertex.attributes,
##     set.edge.attribute, set.vertex.attribute
## The following objects are masked from 'package:stats':
## 
##     decompose, spectrum
## The following object is masked from 'package:base':
## 
##     union
library(intergraph)
### Transfer network from statnet format to igraph format
inetsym <- as.undirected(asIgraph(netsym))
V(inetsym)$name <- netsym %v% "abrev_name"
V(inetsym)$fullname <- network.vertex.names(netsym)
V(inetsym)$role <- rolecat

## Cliques
### Determine the cliques from the network as well as the biggest clique.
clique.number(inetsym)
## [1] 4
cliques(inetsym, min=3)
## [[1]]
## + 3/21 vertices, named, from 9c55256:
## [1] MI TF TG
## 
## [[2]]
## + 3/21 vertices, named, from 9c55256:
## [1] DD DC DI
## 
## [[3]]
## + 3/21 vertices, named, from 9c55256:
## [1] BL BA BC
## 
## [[4]]
## + 3/21 vertices, named, from 9c55256:
## [1] BL BC SA
## 
## [[5]]
## + 3/21 vertices, named, from 9c55256:
## [1] BL BC TG
## 
## [[6]]
## + 3/21 vertices, named, from 9c55256:
## [1] MM MI TF
## 
## [[7]]
## + 4/21 vertices, named, from 9c55256:
## [1] MM MI TF TG
## 
## [[8]]
## + 3/21 vertices, named, from 9c55256:
## [1] MM MI GG
## 
## [[9]]
## + 3/21 vertices, named, from 9c55256:
## [1] MM MI SA
## 
## [[10]]
## + 3/21 vertices, named, from 9c55256:
## [1] MM MI TG
## 
## [[11]]
## + 3/21 vertices, named, from 9c55256:
## [1] MM TF TG
maximal.cliques(inetsym, min=3)
## [[1]]
## + 3/21 vertices, named, from 9c55256:
## [1] BA BL BC
## 
## [[2]]
## + 3/21 vertices, named, from 9c55256:
## [1] DC DD DI
## 
## [[3]]
## + 3/21 vertices, named, from 9c55256:
## [1] GG MM MI
## 
## [[4]]
## + 4/21 vertices, named, from 9c55256:
## [1] TF MM TG MI
## 
## [[5]]
## + 3/21 vertices, named, from 9c55256:
## [1] MM MI SA
## 
## [[6]]
## + 3/21 vertices, named, from 9c55256:
## [1] BC BL TG
## 
## [[7]]
## + 3/21 vertices, named, from 9c55256:
## [1] BC BL SA
largest.cliques(inetsym)
## [[1]]
## + 4/21 vertices, named, from 9c55256:
## [1] TG MM MI TF
## k-Cores
coreness <- graph.coreness(inetsym)
table(coreness)
## coreness
##  1  2  3 
##  1 13  7
maxCoreness <- max(coreness)
maxCoreness
## [1] 3
colors <- rainbow(maxCoreness)
plot(inetsym,vertex.label=coreness,vertex.color=colors[coreness],layout=layout_with_fr)

i1_3 <- inetsym
i2_3 <- induced.subgraph(inetsym, vids=which(coreness > 1))
i3_3 <- induced.subgraph(inetsym, vids=which(coreness > 2))
lay <- layout.fruchterman.reingold(inetsym)
op <- par(mfrow=c(1,3),mar = c(3,0,2,0))
plot(i1_3,layout=lay,vertex.label=coreness,vertex.color=colors[coreness],main="All k-cores")
plot(i2_3,layout=lay[which(coreness > 1),],vertex.label=coreness[which(coreness > 1)],vertex.color=colors[coreness[which(coreness > 1)]],main="k-cores 2-3")
plot(i3_3,layout=lay[which(coreness > 2),],vertex.label=coreness[which(coreness > 2)],vertex.color=colors[coreness[which(coreness > 2)]],main="k-cores 3")

par(op)

## Modularity is a measure that describes how good is a network clusterization
colors <- brewer.pal(5,"Dark2")
roles <- c("C","CR","CT","A","D")
V(inetsym)[V(inetsym)$role == "C"]$color <- colors[1]
V(inetsym)[V(inetsym)$role == "CR"]$color <- colors[2]
V(inetsym)[V(inetsym)$role == "CT"]$color <- colors[3]
V(inetsym)[V(inetsym)$role == "A"]$color <- colors[4]
V(inetsym)[V(inetsym)$role == "D"]$color <- colors[5]

V(inetsym)[V(inetsym)$role == "C"]$group <- 1
V(inetsym)[V(inetsym)$role == "CR"]$group <- 2
V(inetsym)[V(inetsym)$role == "CT"]$group <- 3
V(inetsym)[V(inetsym)$role == "A"]$group <- 4
V(inetsym)[V(inetsym)$role == "D"]$group <- 5

op <- par(mfrow=c(1,1))
plot(inetsym,vertex.color=V(inetsym)$color,vertex.size=10)

## Modularity based on the role of each person
modularity(inetsym, V(inetsym)$group)
## [1] 0
## The result is smaller than 0, which means a bad clusterization result using this method

## Community detection algorithms
cw <- cluster_walktrap(inetsym)
modularity(cw)
## [1] 0.4903549
membership(cw)
## BL BA BC BG MM MI TF TG SA GG CI ML DD DC NP NT SC OA DI PV DR 
##  3  3  3  3  2  2  2  2  2  2  1  1  1  1  1  1  1  1  1  2  2
ceb <- cluster_edge_betweenness(inetsym)
modularity(ceb)
## [1] 0.4903549
membership(ceb)
## BL BA BC BG MM MI TF TG SA GG CI ML DD DC NP NT SC OA DI PV DR 
##  1  1  1  1  2  2  2  2  2  2  3  3  3  3  3  3  3  3  3  2  2
cs <- cluster_spinglass(inetsym)
modularity(cs)
## [1] 0.4903549
membership(cs)
## BL BA BC BG MM MI TF TG SA GG CI ML DD DC NP NT SC OA DI PV DR 
##  2  2  2  2  1  1  1  1  1  1  3  3  3  3  3  3  3  3  3  1  1
cfg <- cluster_fast_greedy(inetsym)
modularity(cfg)
## [1] 0.4695216
membership(cfg)
## BL BA BC BG MM MI TF TG SA GG CI ML DD DC NP NT SC OA DI PV DR 
##  1  1  1  1  3  3  3  3  1  3  2  2  2  2  2  2  2  2  2  1  1
clp <- cluster_label_prop(inetsym)
modularity(clp)
## [1] 0.4185957
membership(clp)
## BL BA BC BG MM MI TF TG SA GG CI ML DD DC NP NT SC OA DI PV DR 
##  1  1  2  1  2  2  2  2  2  2  3  3  3  3  3  3  3  3  3  1  2
cle <- cluster_leading_eigen(inetsym)
modularity(cle)
## [1] 0.464892
membership(cle)
## BL BA BC BG MM MI TF TG SA GG CI ML DD DC NP NT SC OA DI PV DR 
##  1  1  1  1  3  3  3  3  1  3  2  2  2  2  2  2  2  2  2  3  3
cl <- cluster_louvain(inetsym)
modularity(cl)
## [1] 0.4903549
membership(cl)
## BL BA BC BG MM MI TF TG SA GG CI ML DD DC NP NT SC OA DI PV DR 
##  3  3  3  3  1  1  1  1  1  1  2  2  2  2  2  2  2  2  2  1  1
table(V(inetsym)$role,membership(cw))
##    
##     1 2 3
##   1 2 0 0
##   2 6 3 3
##   3 0 0 1
##   4 1 3 0
##   5 0 2 0
compare(as.numeric(factor(V(inetsym)$role)),cw,method="adjusted.rand")
## [1] 0.02816901
compare(cw,ceb,method="adjusted.rand")
## [1] 1
compare(cw,cs,method="adjusted.rand")
## [1] 1
compare(cw,cfg,method="adjusted.rand")
## [1] 0.7075812
op <- par(mfrow=c(3,2),mar=c(3,0,2,0))
plot(ceb, inetsym,vertex.label=V(inetsym)$name,main="Edge Betweenness")
plot(cfg, inetsym,vertex.label=V(inetsym)$name,main="Fastgreedy")
plot(clp, inetsym,vertex.label=V(inetsym)$name,main="Label Propagation")
plot(cle, inetsym,vertex.label=V(inetsym)$name,main="Leading Eigenvector")
plot(cs, inetsym,vertex.label=V(inetsym)$name,main="Spinglass")
plot(cw, inetsym,vertex.label=V(inetsym)$name,main="Walktrap")

par(op)

Chapter 10

## Trying to generate a similar network using Erdos-Renyi method
no_nodes <- length(V(inetsym))
no_edges <- length(E(inetsym))
generated_network <- erdos.renyi.game(n=no_nodes,no_edges,type='gnm')
op <- par(mfrow=c(1,2))
plot(inetsym,vertex.label=NA,vertex.size=5)
plot(generated_network, vertex.label=NA, vertex.size=5)

par(op)

## Trying to generate a similar network using Small-World Model
avg_degree <- no_edges/no_nodes*2
g1 <- watts.strogatz.game(dim=1, size=no_nodes, nei=avg_degree/2, p=.05)
g2 <- watts.strogatz.game(dim=1, size=no_nodes, nei=avg_degree/2, p=.15)
g3 <- watts.strogatz.game(dim=1, size=no_nodes, nei=avg_degree/2, p=.30)
op <- par(mfrow=c(2,2))
plot(inetsym,vertex.label=NA,vertex.size=5)
plot(g1, vertex.label=NA, vertex.size=5)
plot(g2, vertex.label=NA, vertex.size=5)
plot(g3, vertex.label=NA, vertex.size=5)

par(op)

## Trying to generate a similar network using Scale-Free Model
barabasi_network <- barabasi.game(no_nodes, directed=FALSE)
op <- par(mfrow=c(1,2))
plot(inetsym,vertex.label=NA, vertex.size=5)
plot(barabasi_network,vertex.label=NA, vertex.size=5)

par(op)


## Comparing random models with the empirical network
list_network <- c(generated_network, g2, barabasi_network, inetsym)
comparison_table <- data.frame(
  Name = c("Erdos-Renyi", "Small world", "Scale-free model", "Empiric network"),
  Size = c(length(V(generated_network)), length(V(g2)), length(V(barabasi_network)), length(V(inetsym))),
  Density = c(gden(asNetwork(generated_network)),gden(asNetwork(g2)),gden(asNetwork(barabasi_network)),gden(asNetwork(inetsym))),
  Avg_Degree = c(length(E(generated_network))/length(V(generated_network)),length(E(g2))/length(V(g2)),length(E(barabasi_network))/length(V(barabasi_network)),length(E(inetsym))/length(V(inetsym))),
  Transitivity = c(transitivity(generated_network), transitivity(g2), transitivity(barabasi_network), transitivity(inetsym)),
  Isolates = c(sum(degree(generated_network)==0),sum(degree(g2)==0),sum(degree(barabasi_network)==0),sum(degree(inetsym)==0))
)
comparison_table
##               Name Size   Density Avg_Degree Transitivity Isolates
## 1      Erdos-Renyi   21 0.1714286   1.714286    0.2086957        0
## 2      Small world   21 0.1000000   1.000000    0.0000000        1
## 3 Scale-free model   21 0.0952381   0.952381    0.0000000        0
## 4  Empiric network   21 0.1714286   1.714286    0.2500000        0